<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div {
            width: 200px;
            height: 200px;
            background-color: red;
            /* transition: width 4s, height 4s; */
            -o-transition: width 4s, height 4s;
            -webkit-transition: width 4s, height 4s;
        }
        
        div:hover {
            width: 400px;
            height: 400px;
        }
    </style>
</head>

<body>
    <div>

    </div>
</body>

</html>